A213518 - cp's OEIS frontend

A213518 Numbers k such that the triangular number k*(k+1)/2 has 2 different digits in base 10.

n	a(n)
1	4
2	5
3	6
4	7
5	8
6	9
7	12
8	13
9	18
10	24
11	34
12	44
13	58
14	66
15	77
16	100
17	101
18	105
19	109
20	114
21	132
22	141
23	363
24	666
25	714
26	816
27	1000
28	1095
29	1287
30	1332
31	1541
32	3363
33	6666
34	10000
35	10114
36	13332
37	66666
38	100000
39	133332
40	666666
41	1000000
42	1333332
43	6666666
44	10000000
45	13333332
46	33336636
47	66666666
48	100000000

[4, 5, 6, 7, 8, 9, 12, 13, 18, 24, 34, 44, 58, 66, 77, 100, 101, 105, 109, 114, 132, 141, 363, 666, 714, 816, 1000, 1095, 1287, 1332, 1541, 3363, 6666, 10000, 10114, 13332, 66666, 100000, 133332, 666666, 1000000, 1333332, 6666666, 10000000, 13333332, 33336636, 66666666, 100000000]

cp's OEIS Frontend

A213518 Numbers k such that the triangular number k*(k+1)/2 has 2 different digits in base 10.

Table of values

List of values